Whats the best spring-shim combo fo rthe Forge?

[gsrtype1]

Just go the Forge into today ordered it Friday from Streetunit second great experiance with Mark. I figured recucluation was better for long term and I will get Cp-e dp soon and i don't want to spit fuel into the little cat up by vta. It makes a cool sound but I miss my rfl already.. But I am happy with the Forge and going to work with it! Please advise on best sping shim setup It comes with yellow spring installed only no shim.

[hamptotl]

I have the forge but all i have is a CAI i have the blue spring in mine from what i here the blue spring is the best for a near stock car. For what you have in your sig i would recommend the red spring with no shims since you have quite a bit more power than nearly stock. Thats just my recommendation

[gsrtype1]

Thanks! yeah I just tried the blue spring with 1 shim, seems like teh RFL hold boost better, but I try the red spring. Plus its just a "light" ping It doesn't seem lout at all but maybe thats becuase i'm used to the rfl.

[Superstretch18]

Blue spring for near stock boost levels; at 20 psi, you're probably going to need the red spring...

[gsrtype1]

Yeah I gonna try 1 more shim to make 2 on the blue and then give the red a try.

[Hectik1]

Blue with 2 or red spring should do it.

[Superstretch18]

Originally Posted by SilverSpeed3 Blue with 2 or red spring should do...

Hey, that rhymes...

[gsrtype1]

Yeah I gonna try that when I get off work.

[Buildabong]

nothing get rid of that shit its worthless

[gsrtype1]

The Forge is a REEEALLY high quality peice, almost like a peice of jewlry.. I reeally do love th RFL thogh.. miss her already..( ..lol I love the way the throttle reacts works togetheer with the sound of RFL vta. it makes for a great driving experiance. the Forge is quiet by comaprison. Not as involving but still nice.

[phillyb]

PING

[hamptotl]

I love my forge and once you get the set up right you will notice that it really is an awesome piece of course thats just my opinion but i love mine and like having a differant sound. Funny part is having some idiot driving next to thinks you have a normal three then i shift into 3rd at about 4500 rpm and PING all of a sudden they drop back real quick. Have fun with it and i hope once it is set right you dont miss your RFL to much

[gsrtype1]

Yeah it reeeeally holds boost I noticed last night with the blue spring and 1 shim I think i was getting a little compressor surge, and sometimes when I would floor it instead of pinging it would flutter like an hks? So i have just the blue spring and it feels better. But right now i'm only at 19psi when I go higher I may add a shim or 2 a or red spring.

[gsrtype1]

Just ran a couple of arrons and I noticed sometimes it seems to makes a fluttering noise instead of ping, plus the ping seeems reeeeally quiet. I know thats prob cuase i'm used to the rfl but is that normal? Like you floor it and the tires break loose in second and when you let off the gas it has a light flutter instead of ping.

[motocrosser614]

When u heard the flutter gsr did you have any shims in?

[gsrtype1]

Originally Posted by motocrosser614 When u heard the flutter gsr did you have any shims in?

na just blue spring, It did it with 1 shim last night too.

[motocrosser614]

well i dont have near the mods you do but if you put your shim on the top of the spring under the cap you will get flutter and surge. i have AP and sri i run the blue spring only try the red you might like it better

[gsrtype1]

Yeah I'll give it a try, it reeally felt to almost hold to much boost with the blue and a shim though. But I haven tested extensvly..

[gsrtype1]

The Forge is reeally getting nice! 3rd gear feels more torqey I think. I'm assuming its cuase it hoilding boost better.

[Hectik1]

Originally Posted by gsrtype1 The Forge is reeally getting nice! 3rd gear feels more torqey I think. I'm assuming its cuase it hoilding boost better.

That is what's nice about the Forge!

[hamptotl]

Yeha its the shit. I love mine dude. like motocrosser said try moving the shim from bottom to top and give it shot. Good luck and keep us posted

[FreeFlyFreak]

Originally Posted by hamptotl Yeha its the shit. I love mine dude. like motocrosser said try moving the shim from bottom to top and give it shot. Good luck and keep us posted

NO.

No shims on top!

You will partially, possibly totally (with grease), blockoff the boost/vacuum from the top of the piston and the Valve will NOT function as designed.

[motocrosser614]

I honestly would not use any shims i have had the best results with using just the spring for whatever application you run. I said put the shim on the bottom only!!!!!! not the TOP!!!

I repeat if you put a shim on TOP of the spring you will get flutter and surge...no good...flutter is bad for this turbo and surging will make your car jump forward between shifts.

I just wanna be clear and not give incorrect advise. SHIMS GO ON BOTTOM

[gsrtype1]

yeah with just the blue spring runnin 19psi seems to really work good!

[skubidoobie]

Informative thread, have my Forge sitting in front of me right now. Tomorrow I will be installing it on my stock car (waiting for my nano), so I guess just the blue spring for me. Other threads say just go right to blue with 2 shims, but I guess that's not the case. Thanks all, and happy kwanzaa my homies lol.

[BreakTheStatic]

Originally Posted by skubidoobie Informative thread, have my Forge sitting in front of me right now. Tomorrow I will be installing it on my stock car (waiting for my nano), so I guess just the blue spring for me. Other threads say just go right to blue with 2 shims, but I guess that's not the case. Thanks all, and happy kwanzaa my homies lol.

For a stock car, definite;y don't use two shims. I started off with 2 shims when running SRI, FMIC & Piasini tune and was getting quite a bit of surge. I eventually settled on just the blue spring with no shims. Once I installed my turbo-back I went up to 1 shim. But for a bone stock car, use the blue without any shims.

[hamptotl]

Yeah sorry all i defiently fckd that up i ment the bottom apologies to all.

[gsrtype1]

I reeally like the forge now! Hey I do notice I get flutter sometimes even with no shim at 19psi with blue spring. Is this normal? Drivabilty is awsome though really!

[motocrosser614]

you prolly get flutter cause your runnin 19 psi, i sometimes get flutter on the highway in sixth with stock boost switchin lanes it seems pretty normal so i wouldnt think anything bad is goin on. Glad you dig the forge i love mine the ping noise everyone talks of is pretty non existeint now im very happy with my 150$$

[skubidoobie]

Just installed my Forge and Nano today, I love that Mario coin ching sound! More like wooooooschhingg! Blue spring only and all seems good. Will be posting a review soon, uploading pictures to photobucket now.

[08_ms3_gt]

the yellow spring with a shim or two should be sufficient.

i initially had a blue spring with two shims and found that it worked yet i did not believe it fully opened/closed at lower boost levels. this would indicate that the blue spring has a load that is too great for the system at low boost.

i switched to the yellow spring (two shims) and had better function across all boost levels. i did not notice a boost leak or power loss with the yellow spring versus the blue.

i cannot confirm the actual boost via gauge or logging but already have plenty of Forge valve experience with my old car (a 1.8T). i have also read accounts that the better range of function of the yellow spring helps to reduce the turbo/intake temperatures because it opens/closes more effectively for stock boost and helps the turbo to more efficiently spool/decel/'freewheel'.

[MPS]

whats the red spring for ?

[08_ms3_gt]

Originally Posted by MPS whats the red spring for ?

yellow = 15-23psi
blue = 23-30psi
red = 30+psi

the springs are geared to open the valve for differing peak boost levels. the shims slightly increase the 'preload' for the spring, meaning the boost at which it opens is increased slightly.

[phantom3]

I was wondering...
to set up the forge could you not just apply pressure (via a vacc/pressure gun) to the sensing port on the forge, at 1 psi over you desired boost level? (running 18psi set to 19psi). That way you could see if it was opening and if you would require a different spring/ shim combo?

[08_ms3_gt]

Originally Posted by phantom3 I was wondering... to set up the forge could you not just apply pressure (via a vacc/pressure gun) to the sensing port on the forge, at 1 psi over you desired boost level? (running 18psi set to 19psi). That way you could see if it was opening and if you would require a different spring/ shim combo?

yes - people have done so. there is a thread that i started in the 'other' forum where someone did just that - a thread entitled "turbo/intake whine..?"

BUT the Forge has a design that can make it difficult to test - the manifold/vacuum side of the valve has a greater area than the compressor discharge/pressure side UNTIL the valve opens, at which point they have equal areas.

the spring in the valve opens when a necessary force is imposed on it - this force is the pressure difference between the air into the engine and the air from the turbo. when you release the throttle, the air into the engine drops to vacuum, pressure difference increases, valve opens, etc.

the force from either side depends not only on pressure but also on the area upon which that pressure can act. having a larger area on the intake manifold side means that whatever pressure it has influences the valve significantly more prior to opening.

so, yes, you can do a bench test, but it will only be accurate if you can test from both sides of the valve simultaneously.

[MPS]

so what spring is good for my set up ?
FMIC
TBE
CAI
AP 2+ 103j FMIC map

[08_ms3_gt]

you'd prolly want to check your peak boost in order to be sure, but i would guess you are running around 20psi??? your AP should be able to tell you.

given that setup and the assumption that you're running 20psi, i'd lean towards either the yellow spring with two shims or the blue spring with no shims. and, using your AP, you could check the boost pressures with any given setup in order to figure out what works best.

[BreakTheStatic]

Forge had stated that the yellow spring was too soft for even a stock ms3. They recommended using the blue spring to start off with.

[08_ms3_gt]

Originally Posted by BreakTheStatic Forge had stated that the yellow spring was too soft for even a stock ms3. They recommended using the blue spring to start off with.

where's this information? link, please?

going from the psi ratings, i would agree that the yellow spring is a stretch. that being said, adding two shims to the yellow spring increases the peak boost at which it compresses.

given my experience, i stand by my statement that the yellow spring with two shims is a fit for a stock or slightly modified ms3.

the goal with a diverter valve is to configure it such that it opens just above the maximum boost pressure. that way, it does not leak yet has the most efficient function. using too stiff of a spring implies that the valve won't leak BUT it also won't fully open/close which induces wear on the turbo and increases intake charge temperatures.

quote from Rotus8 in the 'other' forum:

I have had an interesting evening. I decided to try to understand the springs/shims in the Forge BPV, but I must say I know a lot more details, but I am not sure it is going to help much. I set up my hand vacuum pump and vacuum gauge so I could suck on the valve manifold nipple and observe the piston moving. I checked out the stock valve first, and then tried every combination of yellow spring, 0, 1, & 2 shims, blue spring, 0, 1, & 2 shims, and just for giggles, the red spring with 0 and 1 shims. I repeated each of the measurements on the yellow and blue springs four times, going through each combination to check for consistency. Man that was a lot of opening and closing the cover and shuffling springs around. First an observation of the construction of the stock VS. the Forge BPV. I did not disassemble the stock valve, but I am almost certain it is simply a diaphram with the manifold vacuum on one side, the boosted air on the other, and a preloaded spring holding it closed. The valve seems to open quite linearly with the pressure differential. Also, it doesn't open very far. The Forge design is much cleverer. When the valve is closed, the manifold vacuum acts on the top of the piston, about 1.5" in diameter. The boosted air acts on the closed piston which is about .75" in diameter. This means that the vacuum has four times the effect on the piston than the boost pressure. Now, when the valve begins to open, the boost pressure is allowed inside the valve and now acts on the full 1.5" in diameter. The effect of this is when the pressure differential reaches the point where the valve starts to open, it opens quickly because of the assist from the boost pressure. It starts to open later though, because the boost pressure is not exerting as much pressure against the preload of the spring. Is this making sense? Anyway, here are the numbers: The stock valve starts to open at 7.8 psi, and is fully open (which isn't very open) at 13.8 psi. The Forge valve starts to open, and is fully open like this: Yellow, 0 shims - start 4.6, full 7.0 Yellow, 1 shim - start 5.0, full 7.6 Yellow, 2 shims - start 5.5, full 8.4 Blue, 0 shims - start 4.3, full 7.5 Blue, 1 shim - start 5.3, full 7.9 Blue, 2 shims - start 6.1, full 9.1 Red, 0 shims - start 7.5, full 13.3 Red, 1 shim - start 8.5, full 13.8 Observations: 1) The yellow with no shims opens at a higher pressure then the blue with no shims, but this is because at least in my set, the yellow spring is longer than the blue one, so starts with higher preload for the same height. This points out that the resting length of the spring has a significant effect on the opening point and there may be manufacturing tolerences here so yours may be different than mine. 2) The stock valve in free air starts to open at 7.8 psi, where for the Forge to start to open at that point, you would have to run the red spring, which has been shown to be much too strong. This blows my idea out of the water - you cannot adjust the spring preload by comparing the simple opening vacuum on the intake manifold the same as the stock valve. The construction of the valves is so different, this just doesn't work. My conclusion is that to adjust the valve properly, you need to put a boost gauge on the boost tube just before the throttle butterfly. You want to adjust the valve preload so it opens just as you close the throttle from WOT with only a small boost spike as that happens. In my opinion you want as light a spring as possible to keep the valve open as long as you can until you get into the thottle again so the turbo keeps free-wheeling. I am now even more convinced the the ideal BPV is electrically operated, bang open and bang closed, based on electronic reading of the throttle plate position and boost pressure. Sorry for the pedantic long-windedness, but I got into it and couldn't stop... I'm out to the garage to put my car back together - I'm gonna try yellow spring and one shim for tomorrow's test drive (um commute).

[BreakTheStatic]

forge bpv - Mazda Forums

ETA on Forge BPVs? - Page 3 - Mazda Forums

Pat from Forge has stated that their numbers were based off of VW/Audi testing and is not a good indicator of performance with the Mazda engines.

If you look at his post in the second link you'll see 15-20psi they recommend the blue. I know that even when I was stock I was seeing around 15psi, so unless yours is boosting lower, you should be running the blue.